Within Commonwealth countries other than Canada, mad typically implies the insane or crazy sense more so than the angry sense.

While within the United States and Canada, the word mad does generally imply anger rather than insanity, such usage is still considered informal. Furthermore, if one is described as having "gone mad" or "went mad", this will unquestionably be taken as denoting insanity, and not anger. Meanwhile, if one "is mad at" something or has "been mad about" something, it will be assumed that they are angered rather than insane. In addition, if the word is understood as being used literally, it will most likely be taken as meaning "insane". Also, in addition to the former, such derivatives as "madness", "madman", "madhouse" and "madly" purely denote insanity, irrespective of whether one is in the Commonwealth or in the United States.